Chainslap - How to get rid!

mf-racing

Hi guys,

This is on my new Trek Fuel EX9 running full 08 XT, with the shadow version of the rear mech.

I'm suffering from really noise chain slap when descending, it’s especially bad in the granny and middle rings, and only slightly better in the big ring. I have a fabric chain stay protector fitted (came with the bike) but it does not seem to dampen the noise that much.

I'm thinking taking a few links out of the chain but when I’m in big/big gears even now the rear mech looks a bit stretched out, so I’m not sure if this is the answer?

Years ago, you could buy chain devices that stopped all this by holding the chain up by the chainstay or extra springs pulling the rear mech back.

Any idea on what I can do? Maybe fitting a better rear mech will help (XTR)?

Cheers
Matt

ratty2k

Not much you can do really, I wrapped an old innertube round the chainstay on my old Trek which helped deaden the noise. Just a case of putting up with it tho' really.

defcone

Have you tried the tension screw on the rear derailleur? If that doesnt work, maybe your chain is too long.

mf-racing

defcone wrote:

Have you tried the tension screw on the rear derailleur? If that doesnt work, maybe your chain is too long.

Nope, is that the B-screw? What does it do?

defcone

Im not sure, on my X-9 rear dérailleur, by tightening that tension screw, the rear dérailleur will extend, giving more tension to the chain.

boyfriday

For what it's worth, i have the xtr shadow mech and it makes not a jot of difference.

Huge rattling chain slap affects me too, so an expensive rear mech will not solve your problems.

I will follow this thread though as i'd be interested in ways of cutting it out.

nicklouse

Go Sram.

i thought the Shadow mechs were also meant to reduce the slap...

S_J_P

The Shadow mech doesn't smack the chainstay in the same way as a standard mech can ('cos the body doesn't sit below the chainstay!) and the spring-tension is a lot higher than on the Deore derailler I had on previously, but the chain can still waft about.

artillerydave

earplugs!

beski

Using big front ring & middle cog on rear helps. & a Lizard Skin on your chain stay